1. Field of the Invention
The present invention relates to a touch sensing apparatus and a method thereof, allowing for a significant reduction in the influence of noise without utilizing complex algorithm and signal processing by detecting the presence or absense of noise by using signals detected from at least two electrodes spaced apart from one another in a panel unit.
2. Description of the Related Art
A touch sensing apparatus such as a touch screen, a touch pad, or the like, an input apparatus attached to a display apparatus to provide an intuitive input method to a user, has recently been widely used in various electronic devices such as portable phones, personal digital assistants (PDAs), navigation apparatuses, and the like. In particular, recently, with an increase in demand for smart phones, the rate at which touch screens have been adopted as touch sensing apparatus capable of providing various input methods in a limited form factor has increased on a day by day basis.
Touch screens used in portable devices may be divided into resistive type touch screens and capacitive type touch screens, according to a method of sensing a touch. The capacitive type touch screen has advantages in that it has a relatively long lifespan and various input methods and gestures may be easily implemented therein, such that use thereof has markedly increased. Particularly, a multi-touch interface may be more easily implemented using the capacitive type touch screen, as compared to the resistive type touch screen, such that it is widely used in devices such as smart phones, and the like.
The touch screen is generally attached to a front surface of the display device and touch sensing devices other than the touch screen are also generally provided in the electronic apparatus. Accordingly, accuracy in sensing a touch may be deteriorated due to noise generated from various other electronic components, e.g., a wireless communications unit, the display device and a power supply device, included in the electronic apparatus. An additional shielding layer may be provided between the display device and the touch screen in order to solve the problem, but in this case, overall light transmittance may be deteriorated and product thickness may be increased.
In Patent Document 1, relating to a capacitive type touch screen panel, a method of directly controlling a touch driving time by using a display apparatus timing signal has been disclosed. In addition, in Patent Document 2, relating to a capacitive type touch screen panel, a method of adjusting a settling period so as to reduce the influence of noise in sensing a touch has been disclosed.